Salt does not melt ice – this is actually the way to make the winter city safe


<スパンクラス="キャプション">Spraying salt on the road is a safety measure.</ span> <span class ="帰属"> <クラス="リンク " href ="https://www.shutterstock.com/image-photo/riga-latvia-2016-november-4-snow-514166065" rel ="nofollow noopener" target ="_空欄" data-ylk ="slk:stoatphoto / Shutterstock.com">  stoatphoto / Shutterstock.com </a> </ span>“src =” https://s.yimg.com/ny/api/res/1.2/eSnD6USBjvUTL_EAetxvGw–/YXBwaWQ9aGlnaGxhbmRlcjt3PTcwNTtoPTQ2Ng–/https://s.yimg.com/uu/api/res/1.2/SvxF – ~ B / aD05NTI7dz0xNDQwO2FwcGlkPXl0YWNoeW9u / https: //media.zenfs.com/en/the_conversation_us_articles_815/57342fd7a3c5b51e1c0cb63d3a668ad8 “data-src =” https://s.yimg.com/ny/api/res/1.2/eSnD6USBjvUTL_EAetxvGw–/YXBwaWQ9aGlnaGxhbmRlcjt3PTcwNTtoPTQ2Ng -/https://s.yimg.com/uu/api/res/1.2/SvxfRZiK2BBGUFphfqBkkA–~B/aD05NTI7dz0xNDQwO2FwcGlkPXl0YWNoeW9u/https://media.zenfs.com/en/the_conversation_us3c</div>
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<p>Brrr … It’s cold over there! Hearing the snowy day coming, the children are flocking to the TV. The grocery store’s bread and milk aisles are empty due to the impending snowstorm. And utility trucks are spraying salt or salt water on the road.</p>
<p>Everyone knows why the first two happen. Kids are excited about school holidays full of hot chocolate and snowmen. Adults stock up on essentials. But what about those tracks?</p>
<p>They work to protect drivers from slippery conditions by spraying rock salt. <a href=Brine solution To prevent the formation of ice. This salt is very similar to the salt at the dinner table. The same sodium chloride, NaCl. There are some unique mixtures containing other salts, such as potassium chloride (KCl) and magnesium chloride (MgCl), but they are not commonly used.

Road salt is not as pure as it is used in food.that is Brownish gray mainly due to mineral contamination.. Exposing the environment to this salt through a spill can have unintended consequences such as: Adverse effects on plants, aquatic animals and wetlands..

But it is a cheap and effective way to protect roads from ice by simple scientific principles. Freezing point depression of solution.. The temperature at which ice becomes the freezing point of pure water is 32 degrees Fahrenheit. Therefore, if there is snow, sleet, or icing rain and the ground is below 32 degrees Fahrenheit, hard ice will form on the streets and sidewalks.

However, if water is mixed with salt, the freezing temperature of the solution will be less than 32 F. Salt impedes the ability of water molecules to form solid ice crystals. The degree of freezing point depression depends on the salt content of the solution.

It is important to note that in order to follow this principle, the salt must be contained in a solution containing liquid water. As a result, many cities spray salt solutions before ice forms.

The salt dumped on the ice depends on the friction of the sun or the tires of the car running over it, first melting the ice and mixing with the salt to make a slash that does not refreeze. Pretreatment with solid salt relies on warmer road surfaces to first melt snow and icing rain, allowing them to mix properly with the salt. This is also the reason why pretreatment of bridges that are colder than other roads usually does not work, and also the reason why the sign “Bridge freezes in front of the road” is displayed.

These salt solutions Lower the freezing temperature of water to about 15F.. So, unfortunately, for those who are facing really cold temporary employers, salting does not remove the ice on their roads.

An alternative strategy used at these low temperatures is to put sand on ice. Sand does not change the melting temperature, it only provides a rough surface to prevent the tire from slipping or slipping.

The science of freezing point depression can be applied to any solution, and many research groups have focused on developing fewer alternatives. Adverse effects on the environment..They are included Additives such as molasses and beet juice.. So you might be looking forward to cleaning not only the white salt but also the pink salt from the bottom of your jeans after a winter walk.

This article will be republished from conversation, A non-profit news site aimed at sharing ideas from academic experts. It was written by: Julie Pollock, University of Richmond..

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Julie Pollock received research funding from the University of Richmond and received the Mary Ease Andrews Award for Cancer Research from the Virginia Academy of Sciences, the Jeffres Memorial Trust, and the Beckman Foundation.